The collection is astounding in its size alone: There are hundreds of artifacts, including a wealth of taxidermy, African art, Alaskan fishing equipment, Stone Age tools, fossils, and various other historic and natural wonders of the world. A moderately close perusal would take several hours.

The building itself is a treasure too. Built from raw black lava rocks, individually stacked, the construction of the circular museum took 30 years. The museum is a family project, separately owned by three generations of Olsen men, all of them collectors. A complete history is available onsite, and a tour of the museum incorporates family history into explanation of the curiosities.

Also onsite is Mammoth Cave, a lava rock cave used by Stone Age settlers. It was discovered by the second Olsen in 1954, who used it to grow mushrooms, and later opened it as a public attraction alongside his museum. In the 1960s the government designated the cave as a Civil Defense Shelter. In the event of Soviet attack, citizens could take refuge in the cavern, just as settlers long before them had. Though the threat of nuclear attack has faded since then, the dirt road leading to the museum still bears the name “Mammoth Cave Civil Defense Shelter Road.”

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